Catalysts and processes for the formation of terminal olefins by ethenolysis

ABSTRACT

The present invention relates generally to catalysts and processes for the formation of terminal olefin(s) from internal olefin(s) via ethenolysis reactions. The ethenolysis reactions may proceed with high conversion, high turnover, and/or high selectivity.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

This invention was made with the support under the following government contract CHE-0554734 awarded by the National Science Foundation. The government has certain rights in the invention.

FIELD OF THE INVENTION

The invention related generally to the preparation of terminal olefins by ethenolysis reactions.

BACKGROUND OF THE INVENTION

Carbon-carbon coupling reactions catalyzed by transition metal catalysts are among the most important reactions of organic synthetic chemistry. In particular, ethenolysis reactions allow for the formation of terminal olefins from internal olefins via a cross-metathesis reaction with ethylene. Efficient ethenolysis of natural products comprising internal olefins such as methyl oleate is attractive as a method of obtaining useful chemicals (e.g., comprising terminal olefins) from biomass. Although many transition metal catalysts are known to catalyze ethenolysis reactions, the reactions are generally plagued with problems of moderate to poor conversion and selectively, as well as limited turnover numbers. In particular, selectively of ethenolysis reactions are often low as undesired products are often produced via competing homo-metathesis reactions. Accordingly, improved catalysts and processes are needed.

SUMMARY OF THE INVENTION

The present invention, in some embodiments, provides methods comprising reacting ethylene and a first species comprising at least one internal olefin in the presence of a transition metal catalyst to produce at least one product comprising a double bond, the double bond comprising a carbon atom from the ethylene and an atom of the first species, wherein the at least one product is formed at a turnover number of at least about 5000, a selectivity of at least about 80%, and a conversion of at least about 70%.

The present invention also provides methods comprising providing a catalyst having the structure:

wherein M is Mo or W, R¹ is aryl, heteroaryl, alkyl, heteroalkyl, optionally substituted, R² and R³ can be the same or different and are hydrogen, alkyl, alkenyl, heteroalkyl, heteroalkenyl, aryl, or heteroaryl, optionally substituted, and R⁴ and R⁵ can be the same or different and are alkyl, heteroalkyl, aryl, heteroaryl, or silyl, optionally substituted, wherein at least one of R⁴ or R⁵ is a ligand containing oxygen bound to M, and reacting ethylene and a first species comprising at least one internal olefin in the presence of the catalyst to produce at least one product comprising a double bond, the double bond comprising a carbon atom from the ethylene and an atom of the first species, wherein the at least one product is formed at a turnover number of at least about 500.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A illustrates an ethenolysis reaction between ethylene and a non-cyclic internal olefin.

FIG. 1B illustrates an ethenolysis reaction between ethylene and a cyclic internal olefin.

FIG. 2 shows non-limiting examples of catalysts for ethenolysis, according to some embodiments of the present invention.

FIG. 3 shows the x-ray crystal structure of a catalyst for ethenolysis reaction, according to a non-limiting embodiment of the present invention.

Other aspects, embodiments, and features of the invention will become apparent from the following detailed description when considered in conjunction with the accompanying drawings. The accompanying figures are schematic and are not intended to be drawn to scale. For purposes of clarity, not every component is labeled in every figure, nor is every component of each embodiment of the invention shown where illustration is not necessary to allow those of ordinary skill in the art to understand the invention. All patent applications and patents incorporated herein by reference are incorporated by reference in their entirety. In case of conflict, the present specification, including definitions, will control.

DETAILED DESCRIPTION

The present invention relates generally to catalysts and processes for the formation of terminal olefin(s) from internal olefin(s) via ethenolysis. Terminal olefins (or alpha-olefins) are important chemicals used as feedstock to produce higher valued end products. Ethenolysis reactions are generally plagued by poor to moderate selectivity, as there usually are competing processes taking place which produce undesired product(s) (e.g., homo- or self-metathesis product(s)). In addition, many catalysts suffer from poor or moderate turnover numbers and/or conversion.

The ethenolysis reactions described herein may proceed with high conversion, high turnover, and/or high selectivity. It is generally believed in the art that during the catalytic cycle of ethenolysis using a transition metal catalyst, a methylidene species (e.g., M=CH₂) may form which, in most cases, is highly unstable and prone to bimolecular decomposition, thereby leading to poor turnover numbers, conversion and/or selectivity. However, one set of catalysts described herein has access to methylidene species which are unexpectedly stable and long lived (e.g., observed in solution for at least about 1 minute, at least about 5 minutes, at least about 10 minutes, at least about 20 minutes, at least about 30 minutes, at least about 1 hour, or more) without appreciable decomposition (e.g., less than about 1%, less than about 3%, less than about 5%, less than about 10%, or less than about 20%, etc., decomposition). The unexpected stability of the methylidene species, in combination with the high reactivity of the methylidene species towards olefins, allows for unanticipated success in promoting ethenolysis reactions with high turnover numbers, high selectivity, and/or high conversion.

The term, “ethenolysis,” as used herein, refers to a metathesis reaction between ethylene (e.g., a molecule of ethylene) and a species comprising at least one internal olefin (e.g., cyclic or non-cyclic) to produce terminal olefin(s). In some embodiments, an ethenolysis reaction involves reacting ethylene and a species comprising an internal olefin (e.g., in the presence of a transition metal catalyst) to produce at least one product comprising a double bond, the double bond comprising a carbon atom from ethylene and an atom (e.g., a carbon atom) of the first species. The species comprising at least one internal olefin may be substituted and/or comprise heteroatoms. As a non-limiting example, FIG. 1A shows an ethenolysis reaction between a non-cyclic species comprising an internal olefin 2 and ethylene 4 to produce species comprising terminal olefins 6 and 8. Products 10 and 12 are undesired homo- or self-metathesis products (e.g., comprising internal olefins). As another non-limiting example, a cyclic species comprising an internal olefin 14 may react with ethylene to produce corresponding product 18, comprising two terminal olefins, as shown in FIG. 1B.

In some embodiments, the ethenolysis reaction may proceed with good selectivity. The term, “selectivity,” as used herein, refers the selectivity of the ethenolysis reaction to form desired product(s) (e.g., terminal olefin(s)) as opposed to undesired product(s) (e.g., homo-metathesis product(s)). In some embodiments, the percent selectivity may be calculated according to the following equation:

${\% \mspace{14mu} {Selectivity}} = {100 \times \left\{ \frac{\left( {{moles}\mspace{14mu} {of}\mspace{14mu} {desired}\mspace{14mu} {{products}(s)}\mspace{14mu} {produced}} \right)}{\left( {{total}\mspace{14mu} {moles}\mspace{14mu} {of}\mspace{14mu} {{product}(s)}\mspace{14mu} {produced}} \right)} \right\}}$

wherein the desired products produced in an ethenolysis reaction are the terminal olefin(s) produced (e.g., 6 and 8 in FIG. 1A) and the total products produced include the terminal olefins (e.g., 6 and 8 in FIG. 1A) and any undesired products such as species comprising internal olefins (e.g., homo-metathesis products 10 and 12 in FIG. 1A). The products may be determined using techniques known to those of ordinary skill in the art (e.g., isolation of reagent, GPC, HPLC, NMR, etc.). As a specific example, in the ethenolysis reaction of methyl oleate, the desired products are the terminal olefins (e.g., 1-decene and methyl-9-decenoate) and the undesired products are the homo- or self-metathesis products of 1-decene and methyl-9-decenoate (e.g., 1,18-dimethyl-9-octadecenedioate and 9-octadecene). In some cases, the ethenolysis reaction may proceed with a selectivity of (e.g., the at least one product of the ethenolysis reaction is formed at a selectivity of) at least about 60%, at least about 70%, at least about 75%, at least about 80%, at least about 85%, at least about 90%, at least about 95%, at least about 97%, at least about 98%, at least about 99%, or more. In some cases, the selectivity is about 70%, about 75%, about 80%, about 85%, about 90%, about 95%, about 97%, about 98%, about 99%, or the like. In some instances, the selectivity is between about 60% and about 99%, between about 70% and about 95%, between about 70% and about 90%, or any other range therein.

In some embodiments, the ethenolysis reaction may proceed with good turnover numbers. The term “turnover number,” as used herein, refers to the number of average times a catalyst is able to promote an ethenolysis reaction. In some embodiments, the turnover number may be calculated according the following equation:

${{Turnover}\mspace{14mu} {number}} = {\% \mspace{14mu} {yield} \times \left\{ \frac{\left( {{moles}\mspace{14mu} {of}\mspace{14mu} {limiting}\mspace{14mu} {reagent}} \right)}{\left( {{moles}\mspace{14mu} {of}\mspace{14mu} {catalyst}} \right)} \right\}}$

wherein the percent yield may be calculated according to the following equation:

${\% \mspace{14mu} {Yield}} = {100 \times {\left\{ \frac{\left( {{moles}\mspace{14mu} {of}\mspace{14mu} a\mspace{14mu} {desired}\mspace{14mu} {product}} \right)}{\left( {{moles}\mspace{14mu} {of}\mspace{14mu} {limiting}\mspace{14mu} {reagent}} \right)} \right\}.}}$

The moles of catalyst may be determined from the weight of catalyst (or catalyst precursor) provided, the moles of limiting reagent (e.g., generally the species comprising at least one internal olefin in ethenolysis reactions) may be determined from the amount of limiting reagent added to reaction vessel, and the moles of a desired product (e.g., moles of a terminal olefin produced such as 6 or 8 in FIG. 1A) which may be determined using techniques known to those of ordinary skill in the art (e.g., isolation of product, GPC, HPLC, NMR, etc.). In some cases, the ethenolysis reaction may proceed at a turnover number of (e.g., the at least one product of the ethenolysis reaction is formed at a turnover number of) at least about 500, at least about 1000, at least about 3,000, at least about 5,000, at least about 10,000, at least about 15,000, at least about 20,000, at least about 25,000, at least about 30,000, at least about 40,000, at least about 50,000, or more. In some cases, the turnover number is between about 5,000, and about 50,000, between about 10,000 and about 30,000, between about 15,000 and about 25,000, or any other ranger therein. The turnover frequency is the turnover number divided by the length of reaction time (e.g., seconds).

In some cases, the ethenolysis reaction may proceed with high conversion. Conversion refers to the percent of the limiting reagent converted to product. In some embodiments, percent conversion may be calculated according to the following equation:

${\% \mspace{14mu} {Conversion}} = {100 - \left\{ \frac{\left( {{final}\mspace{14mu} {moles}\mspace{14mu} {of}\mspace{14mu} {limiting}\mspace{14mu} {reagent}} \right) \times 100}{\left( {{initial}\mspace{14mu} {moles}\mspace{14mu} {of}\mspace{14mu} {limiting}\mspace{14mu} {reagent}} \right)} \right\}}$

where the initial moles of the limiting reagent may be calculated from the amount of limiting reagent added to reaction vessel and the final moles of the limiting reagent may be determined using techniques known to those of ordinary skill in the art (e.g., isolation of reagent, GPC, HPLC, NMR, etc.). In some cases, the ethenolysis reaction may proceed with a conversion of (e.g., the at least one product of the ethenolysis reaction is formed at a conversion of) at least about 60%, at least about 70%, at least about 75%, at least about 80%, at least about 85%, at least about 90%, at least about 95%, at least about 97%, at least about 98%, at least about 99%, or more. In some cases, the conversion is about 70%, about 75%, about 80%, about 85%, about 90%, about 95%, about 97%, about 98%, about 99%, or the like. In some instances, the conversion is between about 60% and about 99%, between about 70% and about 95%, between about 70% and about 90%, or any other range therein.

As mentioned above, in some cases, the ethenolysis reaction may proceed with high turnover numbers, high selectivity, and/or high conversion. In a particular embodiment, the reaction may proceed with a turnover number of at least about 5000, a selectivity of at least about 80%, and/or a conversion of at least about 70%, or will a selectivity of at least about 70% and/or a conversion of at least about 80%. In some cases, the reaction may proceed with a turnover number of at least about 15,000, and a selectivity of at least about 85%, and/or a conversion of at least about 60%, or a selectivity of at least about 60% and/or a conversion of at least about 85%. In other cases, the reaction may proceed with a turnover number of at least about 20,000 and a conversion of at least about 50%. It should be understood, however, that any other combination of turnover numbers, conversion, and/or selectivity as described herein, may be obtained.

The ethenolysis reaction may be carried out using techniques known to those of ordinary skill in the art. In some cases, the reaction may involve exposing a catalyst (e.g., as described herein) to a species comprising at least one internal olefin and ethylene (e.g., an atmosphere of ethylene). In some instances, the reaction mixture may be agitated (e.g., stirred, shaken, etc.). The reaction products may be isolated (e.g., via distillation, column chromatography, etc.) and/or analyzed (e.g., gas liquid chromatography, high performance liquid chromatography, nuclear magnetic resonance, etc.) using commonly known techniques.

Species comprising at least one internal olefins will be known to those of ordinary skill in the art. A species comprising at least one internal olefin may be non-cyclic or cyclic, symmetric or non-symmetric, and/or comprise one or more ethylenic units and/or heteroatoms (e.g., oxygen, nitrogen, silicon, sulfur, phosphorus, etc.). Non-limiting examples of species comprising internal olefins are linear alkyl internal olefins such as C₄-C₃₀olefins (e.g., 2-hexene, 3-hexene, 2-heptene, 3-heptene, etc.), linear internal heteroalkyl olefins such as methyl oleate (e.g., where the desired products are 1-decene and methyl 9-decenoate), and cycloalkenes such as C₄-C₃₀ cycloalkenes (e.g., octene (wherein the product is 1,9-decadiene), cyclopentene (wherein the product is 1,6-heptadiene), cyclododecatriene, etc.)

In some cases, the ethenolysis reaction may be carried out under a pressure of ethylene (e.g., in a high pressure vessel, a Fisher-Porter bottle, etc.) of about 1 atm, about 1.5 atm, about 2 atm, about 4 atm, about 6 atm, about 8 atm, about 10 atm, about 20 atm, about 50 atm, about 100 atm, or the like. In some cases, the pressure of ethylene is between about 1 atm and about 10 atm, between about 2 atm and about 5 atm, or the like.

The ethenolysis reaction may be carried out at any suitable temperature. In some cases, the reaction is carried out at about room temperature (e.g., about 25° C., about 20° C., between about 20° C. and about 25° C., or the like). In some cases, however, the reaction may be carried out at a temperature below or above room temperature, for example, at about −70° C., about −50° C., about −30° C., about −10° C., about −0° C., about 10° C., about 30° C., about 40° C., about 50° C., about 60° C., about 70° C., or the like. In some embodiments, the reaction may be carried out at more than one temperature (e.g., reactants added at a first temperature and the reaction mixture agitated at a second wherein the transition from a first temperature to a second temperature may be gradual or rapid.

As noted, one set of catalysts has been identified in accordance with the invention which provides unexpected results in ethenolysis reactions. In some embodiments, the catalyst provided is a metal complex with the structure:

wherein M is a metal; R¹ is aryl, heteroaryl, alkyl, heteroalkyl, optionally substituted; R² and R³ can be the same or different and are hydrogen, alkyl, alkenyl, heteroalkyl, heteroalkenyl, aryl, or heteroaryl, optionally substituted; and R⁴ and R⁵ can the same or different and are alkyl, heteroalkyl, aryl, or heteroaryl, optionally substituted, or R⁴ and R⁵ are joined together to form a bidentate ligand with respect to M, optionally substituted. In some cases, at least one of R⁴ or R⁵ is a ligand containing oxygen bound to M (e.g., an oxygen-containing ligand) or a ligand containing nitrogen bound to M (e.g., a nitrogen-containing ligand). In some cases, R² is alkyl. In some instances, M is Mo or W.

In a particular embodiment, one of R⁴ and R⁵ is a ligand containing oxygen bound to M (e.g., an oxygen-containing ligand), optionally substituted, and the other is a ligand containing nitrogen bound to M (e.g., a nitrogen-containing ligand), optionally substituted. In some cases, the oxygen-containing ligand and/or the nitrogen-containing ligand may lack a plane of symmetry. In other embodiments, both R⁴ and R⁵ are oxygen-containing ligands.

As used herein, the term “oxygen-containing ligand” may be used to refer to ligands comprising at least one oxygen atom capable of coordinating a metal atom (e.g., R⁴ and/or R⁵). That is, the term refers to a ligand containing oxygen bound to M. In some cases, the term “oxygen-containing ligand” may also describe ligand precursors comprising at least one hydroxyl group, wherein deprotonation of the hydroxyl group results in a negatively charged oxygen atom, which then coordinates a metal atom. The oxygen-containing ligand may be a heteroaryl or heteroalkyl group comprising at least one oxygen ring atom. In some cases, the oxygen atom may be positioned on a substituent of an alkyl, heteroalkyl, aryl, or heteroaryl group. For example, the oxygen-containing ligand may be a hydroxy-substituted aryl group, wherein the hydroxyl group is deprotonated upon coordination to the metal center. The oxygen-containing ligand may be chiral or achiral, and/or monodentate or bidentate. A monodentate ligand is a ligand which binds or coordinates the metal center via one coordination site of the metal only, and/or via one site of the ligand only. A bidentate ligand is a ligand which binds or coordinates the metal center via two coordination sites of the metal and/or via two sites of the ligand (e.g., a dialkoxide ligand). Non-limiting of achiral monodentate oxygen-containing ligands include —OC(CH₃)(CF₃)₂, —OC(CH₃)₂(CF₃), —OC(CH₃)₃, —OSiPh₃, —OAr (Ar=aryl groups such as phenyl, Mes (Mes=2,4,6-Me₃C₆H₂), 2,6-i-Pr₂C₆H₃, HIPT (hexaisopropylterphenyl), TPP (2,3,5,6-Ph₄C₆H), etc.), and the like.

In some cases, an oxygen-containing ligand may be chiral and may be provided as a racemic mixture or a purified stereoisomer. In some embodiments, the chiral, oxygen-containing ligand may be present in at least 80% optical purity, i.e., the oxygen-containing ligand sample contains 90% of one enantiomer and 10% of the other. In some embodiments, the chiral, oxygen-containing ligand may be at least 90% optically pure, at least 95% optically pure, or, in some cases, at least 99% optically pure.

In some cases, the oxygen-containing ligand (e.g., R⁴ or R⁵) lacking a plan of symmetry may comprise the following structure,

wherein R⁷ is aryl, heteroaryl, alkyl, or heteroalkyl, optionally substituted; R⁸ is hydrogen, —OH, halogen, alkyl, heteroalkyl, aryl, heteroaryl, acyl, acyloxy, or —OP, optionally substituted; or, together R⁷ and R⁸ are joined to form a ring, optionally substituted; R⁹ is —OH, —OP, or amino, optionally substituted; R¹⁰ is hydrogen, halogen, alkyl, heteroalkyl, aryl, heteroaryl, or acyl, optionally substituted; each R¹¹, R¹², R¹³, and R¹⁴ can be the same or different and is aryl, heteroaryl, alkyl, heteroalkyl, or acyl, optionally substituted; or, together R¹¹ and R¹² are joined to form a ring, optionally substituted; or, together R¹³ and R¹⁴ are joined to form a ring, optionally substituted; and P is a protecting group. The ring may be an aromatic or a non-aromatic ring. In some embodiments, the ring may be a heterocycle. In some cases, the protecting group may be a Si protecting group (e.g., tert-butyl dimethyl silyl or TBS). In some embodiments, the oxygen-containing ligand may comprise a substituted alkyl group, such as CF₃.

In some embodiments, R⁸ and R⁹ are attached to the biaryl parent structure via a heteroatom, such as an oxygen atom. For example, R⁸ and R⁹ can be —OH, alkoxy, aryloxy, acyloxy, or —OP, where P is a protecting group (e.g., Si protecting group). In some cases, R⁸ is —OP and R⁹ is —OH or amino.

Examples of oxygen-containing ligands lacking a plane of symmetry or nitrogen-containing ligands lacking a plane of symmetry may be a group having the structure:

wherein each R⁷ and R⁸ can be the same or different and is hydrogen, halogen, alkyl, alkoxy, aryl, acyl, or a protecting group, optionally substituted, R¹⁰ is hydrogen, halogen, alkyl, heteroalkyl, aryl, heteroaryl, or acyl, optionally substituted, each R¹¹, R¹², R¹³, and R¹⁴ can be the same or different and is aryl, heteroaryl, alkyl, heteroalkyl, or acyl, optionally substituted, or together R¹¹ and R¹² are joined to form a ring, optionally substituted, or together R¹³ and R¹⁴ are joined to form a ring, optionally substituted, R¹⁵ is alkyl, aryl, or a protection group, optionally substituted, R¹⁶ is hydrogen or an amine protecting group, X may or may not be present and is any non-interfering group, each Z can be the same or different and is (CH₂)_(m), N, O, optionally substituted, n is 0-5, and m is 1-4. In some embodiments, each R⁷ and R⁸ can be the same or different and is hydrogen, halogen, alkyl, alkoxy, aryl, CF₃, Si-tri-alkyl, Si-tri-aryl, Si-alkyl-diphenyl, Si-phenyl-dialkyl, or acyl (e.g., ester), optionally substituted; R¹⁰ is hydrogen, halogen, alkyl, heteroalkyl, aryl, heteroaryl, or acyl, optionally substituted; each R¹¹, R¹², R¹³, and R¹⁴ can be the same or different and is aryl, heteroaryl, alkyl, heteroalkyl, or acyl, optionally substituted; or, together R¹¹ and R¹² are joined to form a ring, optionally substituted; or, together R¹³ and R¹⁴ are joined to form a ring, optionally substituted; R¹⁵ is alkyl, aryl, protecting group Si-trialkyl, Si-triaryl, Si-alkyldiphenyl, Si-phenyldialkyl, or acyl, optionally substituted; R¹⁶ is hydrogen or an amine protecting group; X can be any non-interfering group; each Z can be the same or different and is (CH₂)_(m), N, O, optionally substituted; n is 0-5 (or any range therein); and m is 1-4 (or any range therein). In some cases, each R⁷ and R¹⁰ is the same or different and is halogen, methyl, t-butyl, CF₃, or aryl, optionally substituted.

In one set of embodiments, R⁴ (or R⁵) is a monodentate oxygen-containing ligand comprising or lacking a plane of symmetry, or a nitrogen-containing ligand lacking a plane of symmetry; and R⁵ (or R⁴) is a nitrogen containing ligand having a plane of symmetry. As used herein, a “nitrogen-containing ligand” (e.g., R⁴ and/or R⁵) may be any species capable of binding a metal center via a nitrogen atom. That is, the term refers to a ligand containing nitrogen bound to M. In some cases, the term “nitrogen-containing ligand” may also describe ligand precursors comprising at least one nitrogen group, wherein deprotonation of the nitrogen group results in a negatively charged nitrogen atom, which then coordinates a metal atom. In some instances, the nitrogen atom may be a ring atom of a heteroaryl or heteroalkyl group. In some cases, the nitrogen atom may be a substituted amine group. It should be understood that, in catalyst described herein, the nitrogen-containing ligand may have sufficiently ionic character to coordinate a metal center, such as a Mo or W metal center. Examples of nitrogen-containing ligands (e.g., having a plan of symmetry) include, but are not limited to, pyrrolyl, pyrazolyl, pyridinyl, pyrazinyl, pyrimidinyl, imidazolyl, triazolyl, tetrazolyl, oxazolyl, isoxazolyl, thiazolyl, isothiazolyl, indolyl, indazolyl, carbazolyl, morpholinyl, piperidinyl, oxazinyl, substituted derivatives thereof, and the like. In one embodiment, R⁴ and R⁵ may be pyrrolyl groups. In some embodiments, the nitrogen-containing ligand may be chiral and may be provided as a racemic mixture or a purified stereoisomer. In some instances, the nitrogen-containing ligand having a plane of symmetry may be a group having the structure:

wherein each R⁶ can be the same or different and is hydrogen, alkyl, heteroalkyl, aryl, heteroaryl, optionally substituted; and X may be present or absent and is any non-interfering group. As used herein, the term “non-interfering group,” refers to any group (e.g., an organic group or permissible substituent to an organic group) which does not significantly effect or alter the properties (e.g., catalytic activity, solubility, etc.) of the compound.

In some embodiments, the catalyst may comprise one of the following structures:

wherein R¹⁹ is F, Cl, Br, or I.

In some cases, R¹ may be linked to form a ring with R² or R³. For example, the metal complex may comprise R¹ linked to form a ring with R² or R³ prior to use as a catalyst, and, upon initiation of the catalyst in a metathesis reaction, the linkage between R¹ and R² or R³ may be broken, therefore rendering each of the ligands monodentate. The ring may comprise any number of carbon atoms and/or heteroatoms. In some cases, the cyclic olefin may comprise more than one ring. The ring may comprise at least 4, at least 5, at least 6, at least 7, at least 8, at least 9, at least 10, or more, atoms.

In some cases, R⁴ and R⁵ are joined together to form a chiral, bidentate ligand. In some cases, the ligand may be of at least 80% optical purity. Examples of chiral bidentate ligands include biphenolates and binaphtholates, optionally substituted with alkyl, alkenyl, alkynyl, cycloalkyl, cycloalkenyl, cycloalkynyl, aryl, alkaryl, aralkyl, optionally interrupted or terminated by heteroatoms, carbonyl groups, cyano, NO₂, alkoxy, aryloxy, hydroxy, amino, thioalkyl, thioaryl, sulfur-containing groups, halides, substituted derivatives thereof, and the like. In some cases, the chiral, bidentate ligand may be substituted at positions in proximity of the metal center to impart stereoselectivity to the reactive site of the catalyst.

Catalysts and/or catalyst precursors of the invention may comprise substituted imido groups (e.g., N—R¹). Without wishing to be bound by theory, the imido group may stabilize the organometallic compositions described herein by providing steric protection and/or reducing the potential for bimolecular decomposition. In some embodiments, R¹ may be aryl, heteroaryl, alkyl, or heteroalkyl, optionally substituted. In some cases, R₁ is aryl or alkyl. In some cases, R¹ may be selected to be sterically large or bulky, including phenyl groups, substituted phenyl groups (e.g., 2,6-disubstituted phenyls, 2,4,6-trisubstituted phenyls), polycyclic groups (e.g., adamantyl), or other sterically large groups. In some embodiments, R¹ may be 2,6-dialkylphenyl, such as 2,6-diisopropylphenyl. For example, in some embodiments, R¹ is

wherein each R¹⁷ can be the same or different and is hydrogen, halogen, alkyl, heteroalkyl (e.g., alkoxy), aryl, acyl, or —OP, optionally substituted, where P is a protecting group.

In some embodiments, R¹ is

R² is CMe₂Ph or CMe₃; and R⁴ is an enantiomer of the following structure,

wherein each R¹⁷ is the same or different and is halogen, methyl, t-butyl, CF₃, or aryl, optionally substituted, R⁵ is a nitrogen-containing ligand having a plane of symmetry, and R⁷, R¹⁰, and R¹⁵ are as described herein.

Catalysts and/or catalyst precursors of the invention may further comprise substituted alkylidene groups (e.g., CR²R³). The alkylidene groups may be mono-substituted (e.g., one of R² and R³ is hydrogen) or di-substituted with, for example, alkyl, heteroalkyl, aryl, or heteroaryl groups, optionally substituted. In some cases, the alkylidene may be mono-substituted with, for example, t-butyl, dimethylphenyl, or the like. In some cases, R² is CMe₂Ph or CMe₃, and R³ is hydrogen.

In some cases, catalysts comprising one or more sterically large ligands may be synthesized. For example, at least one of R¹—R⁵ may contain sterically large groups, such as tert-butyl, isopropyl, phenyl, naphthyl, adamantyl, substituted derivatives thereof, and the like. Sterically large ligands may also include ligands comprising substituents positioned in close proximity to the metal center when the ligand is bound to the metal.

In some cases, the catalyst comprises a stereogenic metal atom. As used herein, the term “stereogenic metal atom” is given its ordinary meaning, and refers to a metal atom coordinated by at least two ligands (e.g., at least four ligands), wherein the ligands are arranged about the metal atom such that the overall structure (e.g., metal complex) lacks a plane of symmetry with respect to the metal atom. In some cases, the stereogenic metal atom may be coordinated by at least three ligands, at least four ligands, at least five ligands, at least six ligands, or more. In a particular embodiment, the stereogenic metal atom may be coordinated by four ligands. Metal complexes comprising a stereogenic metal center may provide sufficient space specificity at a reaction site of the metal complex, such that a molecular substrate having a plane of symmetry may be reacted at the reaction site to form a product that is free of a plane of symmetry. That is, the stereogenic metal center of the metal complex may impart sufficient shape specificity to induce stereogenicity effectively, producing a chiral, molecular product.

In some cases, when the catalyst comprises a stereogenic metal atom, and two or more ligands that bind the metal atom, each ligand associated with the metal complex comprises an organic group. The ligands may be monodentate ligands, i.e., the ligands bind the stereogenic metal atom via one site of the ligand (e.g., a carbon atom or a heteroatom of the ligand). In some cases, a monodentate ligand may bind the metal center via a single bond or a multiple bond. In some cases, the metal complex comprises at least one ligand lacking a plane of symmetry. That is, at least one ligand bound to the stereogenic metal atom is a chiral ligand. In some cases, the metal complex comprises an oxygen-containing ligand, including chiral and/or achiral oxygen-containing ligands. In some cases, the metal complex comprises a nitrogen-containing ligand, including chiral and/or achiral nitrogen-containing ligands. For example, the ligand may be a chiral or achiral nitrogen heterocycle, such as a pyrrolide. In some cases, the metal atom may be bound to at least one carbon atom. In some embodiments, the catalyst comprises the metal complex in a diastereomeric ratio greater than 1:1, greater than about 5:1, greater than about 7:1, greater than about 10:1, greater than about 20:1, or, in some cases, greater.

As suitable, the catalysts employed in the present invention may involve the use of metals which can mediate a particular desired chemical reaction. In general, any transition metal (e.g., having d electrons) may be used to form the catalyst, e.g., a metal selected from one of Groups 3-12 of the periodic table or from the lanthanide series.

However, in some embodiments, the metal may be selected from Groups 3-8, or, in some cases, from Groups 4-7. In some embodiments, the metal may be selected from Group 6. According to the conventions used herein, the term “Group 6” refers to the transition metal group comprising chromium, molybdenum, and tungsten. In some cases, the metal is molybdenum or tungsten. In some embodiments, the metal is not ruthenium. It may be expected that these catalysts will perform similarly because they are known to undergo similar reactions, such as metathesis reactions. However, the different ligands are thought to modify the catalyst performance by, for example, modifying reactivity, and preventing undesirable side reactions. In a particular embodiment, the catalyst comprises molybdenum. Additionally, the present invention may also include the formation of heterogeneous catalysts containing forms of these elements.

In some cases, a catalyst may be a Lewis base adduct. The terms “Lewis base” and “Lewis base adduct” are known in the art and refer to a chemical moiety capable of donating a pair of electrons to another chemical moiety. For example, the metal complex may be combined with tetrahydrofuran (THF), wherein at least one THF molecules coordinate the metal center to form a Lewis base adduct. In some cases, the Lewis base adduct may be PMe₃. In some embodiments, the catalyst may be formed and stored as a Lewis base adduct, and may be “activated” in a subsequent reaction step to restore the catalyst that does not comprise a Lewis base adduct.

Those of ordinary skill in the art will be aware of methods to synthesize catalysts described herein for use in an ethenolysis reaction. The catalysts may be isolated, or may be formed in situ and utilized in a subsequent reaction (e.g. one-pot reaction). The term “one-pot” reaction is known in the art and refers to a chemical reaction which can produce a product in one step which may otherwise have required a multiple-step synthesis, and/or a chemical reaction comprising a series of steps that may be performed in a single reaction vessel. One-pot procedures may eliminate the need for isolation (e.g., purification) of catalysts and/or intermediates, while reducing the number of synthetic steps and the production of waste materials (e.g., solvents, impurities). Additionally, the time and cost required to synthesize catalysts and/or other products may be reduced. In some embodiments, a one-pot synthesis may comprise simultaneous addition of at least some components of the reaction to a single reaction chamber. In one embodiment, the one-pot synthesis may comprise sequential addition of various reagents to a single reaction chamber.

In some embodiments, a catalyst having the structure (I) where M is M or W may be prepared according to the following procedure. Molybdate or tungstate, for example ammonium molybdate (e.g., (NH₄)₂Mo₂O₇), alkylammonium molybdate (e.g., [Mo₈O₂₆][CH₃N(C₈H₁₇)₃]₄, [Mo₈O₂₆][HN(C₁₂H₂₅)₃]₄), or their equivalent, may be combined under an inert atmosphere with amine of the general formula NHXR¹, where R¹ is as defined herein, and where X is hydrogen or trimethylsilyl (e.g., (CH₃)₃SiNHAr, where Ar is an aryl or heteroaryl group). A compound capable of deprotonating NHXR¹, for example, triethylamine, pyridine, substituted pyridine or other equivalent nitrogen bases and halogenating or triflating agents (e.g., Me₃SiCl, Me₃SiBr, Me₃SiSO₃CF₃ or their equivalent) may be added to the reaction mixture. A suitable solvent may be employed which may or may not contain an equivalent amount of coordinating Lewis base (e.g., 1,2-dimethoxyethane (DME), tetrahydrofuran (THF), pyridine, quinuclidine, (R)₂PCH₂CH₂P(R)₂, and P(R)₃ where R=alkyl, aryl), and the reaction mixture may be heated to approximately 60-70° C. for at least about 6 hours under an inert atmosphere (e.g., a nitrogen atmosphere), thereby yielding Mo(NR¹)₂(halogen)₂(Lewis base)_(x) where x is 0, 1 or 2.

The reaction product may be retained in solution or isolated as a solid by the evaporation of the volatile components from solution using distillation techniques.

Treatment of the compound with two equivalents of a Grignard or lithium reagent (or equivalent), such as ClMgCHR²R³, may lead to the production of an intermediate, having the general formula M(NR¹)₂(CHR²R³)₂, where R¹, R² and R³ have been previously defined. This complex may then be treated with three equivalents of a strong acid, such as triflic acid (HOSO₂CF₃), in 1,2-dimethoxyethane (DME, or other suitable solvent), thereby generating a six coordinate complex, M(NR¹)(CR²R³)(OSO₂CF₃)₂.(DME) (or other equivalent). One equivalents of YR⁴ and YR⁵ (where R⁴ and R⁵ are as previously defined and Y is H, Li, Na, K, etc.) or two equivalents of YR⁴ (when R⁴ and R⁵ are the same) or one equivalent of a bidentate ligand (when R⁴ and R⁵ are joined together to form a bidentate ligands) may be reacted with this complex to yield a catalyst having a structure M(NR¹)(CR²R³)(R⁴)(R⁵).

In some embodiments, the catalyst may be formed and isolated or generated in situ from a catalyst precursor having the structure (II)

wherein M is Mo or W; R¹ is alkyl, heteroalkyl, aryl, or heteroaryl, optionally substituted; R² and R³ can be the same or different and are hydrogen, alkyl, alkenyl, heteroalkyl, heteroalkenyl, aryl, or heteroaryl, optionally substituted; R²⁰ and R²¹ can be the same or different and are heteroalkyl or heteroaryl, optionally substituted, or R²⁰ and R²¹ are joined together to form a bidentate ligand with respect to M, optionally substituted; and wherein R²⁰ and R²¹ each comprise at least one nitrogen atom (e.g., are nitrogen-containing ligands). In some cases, R²⁰ and R²¹ each coordinate M via a nitrogen atom. For example, R²⁰ and R²¹ may both be pyrrolyl groups which coordinate the metal via the nitrogen atoms of the pyrrolyl ring. The nitrogen-containing ligand may be selected to interact with an oxygen-containing ligand such that an oxygen-containing ligand can readily replace an nitrogen-containing ligand to generate the catalyst.

As shown by the illustrative embodiment in Scheme 1, a catalyst may be formed from catalyst precursor (II) by reacting the catalyst precursor with an oxygen-containing ligand (e.g., R⁴ and R⁵) such that the oxygen-containing ligand replaces R²⁰ and R²¹ to form the catalyst having the structure (III), wherein R²⁰ and R²¹, in protonated or non-protonated form, may be released. R⁴ and R⁵ may be oxygen-containing ligands or R⁴ and R⁵ may be joined together to form a bidentate, oxygen-containing ligand. In some embodiments, only one of R²⁰ or R²¹ is reacted with an oxygen-containing ligand to form a catalyst, for example, having the structure (IV) or (V), as shown in Scheme I.

In some cases, the oxygen-containing ligand may be in a protonated form prior to coordinating the metal center, and may then have sufficiently ionic character (e.g., may be deprotonated) upon coordination to the metal center. Similarly, the nitrogen-containing ligand may be in a deprotonated form when bound to the metal center, and may become protonated upon release from the metal center. For example, R²⁰ and R²¹ may be pyrrolyl groups coordinating the metal center such that, upon exposure of the catalyst precursor to an oxygen-containing ligand such as biphenolate, the biphenolate ligand may replace the pyrrolyl groups to form the catalyst, resulting in the release of two equivalents of pyrrole. Ligands of the present invention may be described using nomenclature consistent with their protonated or deprotonated forms, and, in each case, it should be understood that the ligand will adopt the appropriate form to achieve its function as, for example, either a ligand bound to a metal center or an inert species in the reaction mixture. For example, in an illustrative embodiment, the term “pyrrolyl” may be used to describe a deprotonated, anionic pyrrole group which may coordinate a metal center, while the term “pyrrole” may be used to describe a neutral pyrrole group which does not coordinate the metal center but may be present in solution as an inert species that does not react with other components in the reaction mixture.

In cases where the catalyst may be generated in situ in order to carry out a chemical reaction, the first, nitrogen-containing ligand may be selected such that, upon replacement by an oxygen-containing ligand, the nitrogen-containing ligands or protonated versions thereof do not interfere with the chemical reaction. That is, R²⁰ and R²¹ may be selected such that the released R²⁰ and/or R²¹ groups may not interfere with subsequent reactions that may involve the catalyst or may not react with any other species in the reaction. In some cases, the R²⁰ and R²¹ groups may be released in protonated form (e.g., H—R²⁰ and H—R²¹, or H₂(R²⁰—R²¹)) but may be similarly inert to other species or reagents, including those involved in subsequent reactions. Those of ordinary skill in the art would be able to select the appropriate nitrogen-containing ligand(s) (e.g., R²⁰ and R²¹) suitable for use in a particular application, e.g., such that the released nitrogen-containing ligand(s) do not contain carbon-carbon double bonds which may react with the generated olefin metathesis catalyst.

In some embodiments, a catalyst comprising a stereogenic metal center may be produced by reacting an organometallic composition (e.g., a catalyst precursor) having a plane of symmetry with a monodentate ligand lacking a plane of symmetry, to produce a catalyst comprising a stereogenic metal atom. In some cases the method may comprise reacting a racemic mixture of an organometallic composition comprising a stereogenic metal center with a monodentate ligand lacking a plane of symmetry, to produce a metal complex comprising a stereogenic metal atom. The metal complex may comprise two or more ligands, wherein each ligand binds the stereogenic metal atom via one bond, i.e., each ligand is a monodentate ligand. In some cases, the method may comprise providing a catalyst precursor comprising an organometallic composition having a plane of symmetry and including two or more ligands, in a reaction vessel. At least one ligand may be replaced by a monodentate ligand (e.g., oxygen-containing or nitrogen-containing ligand), thereby synthesizing a metal complex comprising the stereogenic metal atom.

In some cases, the methods described herein may be performed in the absence of solvent (e.g., neat). In some cases, the methods may comprise one or more solvents. Examples of solvents that may be suitable for use in the invention include, but are not limited to, benzene, p-cresol, toluene, xylene, mesitylene, diethyl ether, glycol, petroleum ether, hexane, cyclohexane, pentane, dichloromethane (or methylene chloride), chloroform, carbon tetrachloride, dioxane, tetrahydrofuran (THF), dimethyl sulfoxide, dimethylformamide, hexamethyl-phosphoric triamide, ethyl acetate, pyridine, triethylamine, picoline, mixtures thereof, or the like.

As used herein, the term “reacting” refers to the formation of a bond between two or more components to produce a compound. In some cases, the compound is isolated. In some cases, the compound is not isolated and is formed in situ. For example, a first component and a second component may react to form one reaction product comprising the first component and the second component joined by a covalent bond (e.g., a bond formed between a ligand and a metal, or a bond formed between two substrates in a metathesis reaction). That is, the term “reacting” does not refer to the interaction of solvents, catalysts, bases, ligands, or other materials which may serve to promote the occurrence of the reaction with the component(s).

As used herein, the term “organic group” refers to any group comprising at least one carbon-carbon bond and/or carbon-hydrogen bond. For example, organic groups include alkyl groups, aryl groups, acyl groups, and the like. In some cases, the organic group may comprise one or more heteroatoms, such as heteroalkyl or heteroaryl groups. The organic group may also include organometallic groups. Examples of groups that are not organic groups include —NO or —N₂. The organic groups may be optionally substituted, as described below.

The term “organometallic” is given its ordinary meaning in the art and refers to compositions comprising at least one metal atom bound to one or more than one organic ligands. In some cases, an organometallic compound may comprise a metal atom bound to at least one carbon atom.

The term “chiral” is given its ordinary meaning in the art and refers to a molecule that is not superimposable with its mirror image, wherein the resulting nonsuperimposable mirror images are known as “enantiomers” and are labeled as either an (R) enantiomer or an (S) enantiomer. Typically, chiral molecules lack a plane of symmetry.

The term “achiral” is given its ordinary meaning in the art and refers to a molecule that is superimposable with its mirror image. Typically, achiral molecules possess a plane of symmetry.

The phrase “protecting group” as used herein refers to temporary substituents which protect a potentially reactive functional group from undesired chemical transformations. Examples of such protecting groups include esters of carboxylic acids, silyl ethers of alcohols, and acetals and ketals of aldehydes and ketones, respectively. A “Si protecting group” is a protecting group comprising a Si atom, such as Si-trialkyl (e.g., trimethylsilyl, tributylsilyl, t-butyldimethylsilyl), Si-triaryl, Si-alkyl-diphenyl (e.g., t-butyldiphenylsilyl), or Si-aryl-dialkyl (e.g., Si-phenyldialkyl). Generally, a Si protecting group is attached to an oxygen atom. The field of protecting group chemistry has been reviewed (e.g., see Greene, T. W.; Wuts, P. G. M. Protective Groups in Organic Synthesis, 2^(nd) ed.; Wiley: New York, 1991).

As used herein, the term “alkyl” is given its ordinary meaning in the art and may include saturated aliphatic groups, including straight-chain alkyl groups, branched-chain alkyl groups, cycloalkyl (alicyclic) groups, alkyl substituted cycloalkyl groups, and cycloalkyl substituted alkyl groups. In certain embodiments, a straight chain or branched chain alkyl has about 30 or fewer carbon atoms in its backbone (e.g., C₁-C₃₀ for straight chain, C₃-C₃₀ for branched chain), and alternatively, about 20 or fewer. Likewise, cycloalkyls have from about 3 to about 10 carbon atoms in their ring structure, and alternatively about 5, 6 or 7 carbons in the ring structure. In some embodiments, an alkyl group may be a lower alkyl group, wherein a lower alkyl group comprises 10 or fewer carbon atoms in its backbone (e.g., C₁-C₁₀ for straight chain lower alkyls).

The term “heteroalkyl” is given its ordinary meaning in the art and refers to alkyl groups as described herein in which one or more atoms is a heteroatom (e.g., oxygen, nitrogen, sulfur, and the like). Examples of heteroalkyl groups include, but are not limited to, alkoxy, poly(ethylene glycol)-, alkyl-substituted amino, tetrahydrofuranyl, piperidinyl, morpholinyl, etc.

The term “aryl” refers to aromatic carbocyclic groups, optionally substituted, having a single ring (e.g., phenyl), multiple rings (e.g., biphenyl), or multiple fused rings in which at least one is aromatic (e.g., 1,2,3,4-tetrahydronaphthyl, naphthyl, anthryl, or phenanthryl). That is, at least one ring may have a conjugated pi electron system, while other, adjoining rings can be cycloalkyls, cycloalkenyls, cycloalkynyls, aryls, and/or heterocyclyls. The aryl group may be optionally substituted, as described herein. “Carbocyclic aryl groups” refer to aryl groups wherein the ring atoms on the aromatic ring are carbon atoms. Carbocyclic aryl groups include monocyclic carbocyclic aryl groups and polycyclic or fused compounds (e.g., two or more adjacent ring atoms are common to two adjoining rings) such as naphthyl groups. In some cases, the aryl groups may include monocyclic carbocyclic aryl groups and polycyclic or fused compounds (e.g., two or more adjacent ring atoms are common to two adjoining rings) such as naphthyl group. Non-limiting examples of aryl groups include phenyl, naphthyl, tetrahydronaphthyl, indanyl, indenyl, and the like.The term “heteroaryl” is given its ordinary meaning in the art and refers to aryl groups as described herein in which one or more atoms is a heteroatom (e.g., oxygen, nitrogen, sulfur, and the like), optionally substituted. Examples of aryl and heteroaryl groups include, but are not limited to, phenyl, pyrrolyl, furanyl, thiophenyl, imidazolyl, oxazolyl, thiazolyl, triazolyl, pyrazolyl, pyridinyl, pyrazinyl, pyridazinyl and pyrimidinyl, and the like.

It will also be appreciated that aryl and heteroaryl moieties, as defined herein, may be attached via an aliphatic, alicyclic, heteroaliphatic, heteroalicyclic, alkyl or heteroalkyl moiety and thus also include -(aliphatic)aryl, -(heteroaliphatic)aryl, -(aliphatic)heteroaryl, -(heteroaliphatic)heteroaryl, -(alkyl)aryl, -(heteroalkyl)aryl, -(heteroalkyl)aryl, and -(heteroalkyl)-heteroaryl moieties. Thus, as used herein, the phrases “aryl or heteroaryl” and “aryl, heteroaryl, (aliphatic)aryl, -(heteroaliphatic)aryl, -(aliphatic)heteroaryl, -(heteroaliphatic)heteroaryl, -(alkyl)aryl, -(heteroalkyl)aryl, -(heteroalkyl)aryl, and -(heteroalkyl)heteroaryl” are interchangeable.

The term “olefin,” as used herein, refers to any species having at least one ethylenic double bond such as normal and branched chain aliphatic olefins, cycloaliphatic olefins, aryl substituted olefins and the like. Olefins may comprise terminal double bond(s) (“terminal olefin”) and/or internal double bond(s) (“internal olefin”) and can be cyclic or acyclic, linear or branched, optionally substituted. The total number of carbon atoms can be from 1 to 100, or from 1 to 40; the double bonds may be unsubstituted or mono-, bi-, tri- or tetrasubstituted.

The term “cyclic olefin,” as used herein, refers to any cyclic species comprising at least one ethylenic double bond in a ring. The atoms of the ring may be optionally substituted. The ring may comprise any number of carbon atoms and/or heteroatoms. In some cases, the cyclic olefin may comprise more than one ring. A ring may comprise at least 3, at least 4, at least 5, at least 6, at least 7, at least 8, or more, atoms. Non-limiting examples of cyclic olefins include norbornene, dicyclopentadiene, bicyclo compounds, oxabicyclo compounds, and the like, all optionally substituted. “Bicyclo compounds” are a class of compounds consisting of two rings only, having two or more atoms in common. “Oxabicyclo compounds” are a class of compounds consisting of two rings only, having two or more atoms in common, wherein at least one ring comprises an oxygen atom. The terms “carboxyl group,” “carbonyl group,” and “acyl group” are recognized in the art and can include such moieties as can be represented by the general formula:

wherein W is H, OH, O-alkyl, O-alkenyl, or a salt thereof. Where W is O-alkyl, the formula represents an “ester.” Where W is OH, the formula represents a “carboxylic acid.” The term “carboxylate” refers to an anionic carboxyl group. In general, where the oxygen atom of the above formula is replaced by sulfur, the formula represents a “thiolcarbonyl” group. Where W is a S-alkyl, the formula represents a “thiolester.” Where W is SH, the formula represents a “thiolcarboxylic acid.” On the other hand, where W is alkyl, the above formula represents a “ketone” group. Where W is hydrogen, the above formula represents an “aldehyde” group.

As used herein, the term “halogen” or “halide” designates —F, —Cl, —Br, or —I.

The term “alkoxy” refers to the group, —O-alkyl.

The term “aryloxy” refers to the group, —O-aryl.

The term “acyloxy” refers to the group, —O-acyl.

The term “arylalkyl,” as used herein, refers to an alkyl group substituted with an aryl group.

The terms “amine” and “amino” are art-recognized and refer to both unsubstituted and substituted amines, e.g., a moiety that can be represented by the general formula: N(R′)(R″)(R′″) wherein R′, R″, and R′″ each independently represent a group permitted by the rules of valence.

The term “dialkyl amine” is art-recognized and can be represented by the general formula: N(R′)(R″)⁻, wherein R′ and R″ are alkyl groups.

An “alkoxide” ligand herein refers to a ligand prepared from an alcohol, in that removing the hydroxyl proton from an alcohol results in a negatively charged alkoxide.

As used herein, the term “substituted” is contemplated to include all permissible substituents of organic compounds, “permissible” being in the context of the chemical rules of valence known to those of ordinary skill in the art. In some cases, “substituted” may generally refer to replacement of a hydrogen atom with a substituent as described herein. However, “substituted,” as used herein, does not encompass replacement and/or alteration of a key functional group by which a molecule is identified, e.g., such that the “substituted” functional group becomes, through substitution, a different functional group. For example, a “substituted phenyl” group must still comprise the phenyl moiety and cannot be modified by substitution, in this definition, to become, e.g., a cyclohexyl group. In a broad aspect, the permissible substituents include acyclic and cyclic, branched and unbranched, carbocyclic and heterocyclic, aromatic and nonaromatic substituents of organic compounds. Illustrative substituents include, for example, those described herein. The permissible substituents can be one or more and the same or different for appropriate organic compounds. For example, a substituted alkyl group may be CF₃. For purposes of this invention, the heteroatoms such as nitrogen may have hydrogen substituents and/or any permissible substituents of organic compounds described herein which satisfy the valencies of the heteroatoms. This invention is not intended to be limited in any manner by the permissible substituents of organic compounds.

Examples of substituents include, but are not limited to, alkyl, aryl, arylalkyl, cyclic alkyl, heterocycloalkyl, hydroxy, alkoxy, aryloxy, perhaloalkoxy, arylalkoxy, heteroaryl, heteroaryloxy, heteroarylalkyl, heteroarylalkoxy, azido, amino, halogen, alkylthio, oxo, acylalkyl, carboxy esters, carboxyl, -carboxamido, nitro, acyloxy, aminoalkyl, alkylaminoaryl, alkylaryl, alkylaminoalkyl, alkoxyaryl, arylamino, arylalkylamino, alkylsulfonyl, -carboxamidoalkylaryl, -carboxamidoaryl, hydroxyalkyl, haloalkyl, alkylaminoalkylcarboxy-, aminocarboxamidoalkyl-, cyano, alkoxyalkyl, perhaloalkyl, arylalkyloxyalkyl, and the like.

The following examples are intended to illustrate certain embodiments of the present invention, but do not exemplify the full scope of the invention.

EXAMPLE 1

The following example describes the use of a series of catalysts for ethenolysis reactions.

MonoAryloxide-Pyrrolide (MAP) olefin metathesis catalysts 1 and 2 (shown in FIG. 2) can be prepared through addition of a phenol to a bispyrrolide species. In the process of studying related tungsten MAP complexes, it was noticed that some methylidene species were unusually stable, yet highly reactive. For example, a 0.04 M solution of W(NAr)(CH₂)(O-2,3,5,6-Ph₄C₆H)(Me₂Pyr) (Me₂Pyr=2,5-dimethylpyrrolide) in toluene-d⁸ could be heated to 80° C. without causing significant decomposition in a period of ˜1 hour. The stability of methylidene species is likely to be an important feature of MAP species that are especially efficient in a reaction in which ethylene is present. Without wishing to be bound by theory, the long-lived, reactive methylidene species and lability of unsubstituted metallacyclobutane intermediates suggest that efficient ethenolysis of internal linear or cyclic olefins may be possible. Efficient ethenolysis of natural products such as methyl oleate is attractive as a method of obtaining useful chemicals from biomass.

In this non-limiting example, exposure of catalyst 1a Mo(NAr)(CHC(CH₃)₂Ph))(Me₂Pyr)(OBitet), shown in FIGS. 2) to 1 atm of ethylene has been shown to lead to mixtures that contain the two diastereomers of 1a, the two diastereomers of Mo(NAr)(CH₂)(Me₂Pyr)(OBitet), the unsubstituted molybdacyclobutane, Mo(NAr)(CH₂CH₂CH₂)(Me₂Pyr)(OBitet), and CH₂═CHCMe₂Ph, along with ethylene (OBitet is the aryloxide shown in FIG. 2 in compound 1a). A reaction between Mo(NAr)(CHCMe₃)(Me₂Pyr)(OBitet) and ethylene resulted in the formation of a molybdacyclobutane complex, Mo(NAr)(CH₂CH₂CH₂)(Me₂Pyr)(OBitet). The complex was isolated at −30° C. in the presence of ethylene (1 atm). An X-ray structural study reveals it to have the trigonal bipyramid (TBP) structure shown in FIG. 3, one that is virtually identical to the structure found for W(NAr)(CH₂CH₂CH₂)(Me₂Pyr)(OBitet). Specifically, FIG. 3 shows the POV-ray drawing of Mo(NAr)(C₃H₆)(Me₂Pyr)(OBitet). Thermal ellipsoids are displayed at 50% probability level. Hydrogen atoms were omitted for clarity. Molybdacyclobutane species are especially rare because they lose an olefin readily. To the best of the inventor's knowledge only one other molybdacyclobutane, a square pyramidal bis-t-butoxide species, has been structurally characterized. Metallacyclobutanes that have a TBP structure are proposed to lose an olefin more readily than a SP species. Mo(NAr)(CH₂CH₂CH₂)(Me₂Pyr)(OBitet) releases ethylene readily when an ethylene atmosphere is removed to give mixtures of the two diastereomers of Mo(NAr)(CH2)(Me₂Pyr)(OBitet). In some cases, the two diastereomers of Mo(NAr)(CH₂)(Me₂Pyr)(OBitet) were observed to decompose in the absence of ethylene over a period of 1-2 days.

Ethenolysis (employing 99.5% pure ethylene) of methyl oleate (Table 1) initiated by 1a at room temperature yielded essentially only 1-decene (1D) and methyl-9-decenoate (M9D) with a selectivity of >99% and yields up to 95% (entries 1-4). (The other possible products are 1,18-dimethyl-9-octadecenedioate and 9-octadecene.) The highest turnovers are found at the higher pressures (see entries 3 and 4). Without wishing to be bound by theory, all results may be consistent with time dependent catalyst decomposition and a (low) solubility of ethylene in methyl oleate that limits conversion at low pressures. The catalysts shown in entries 5-7 produce product with lower selectivities and yields. An OBitet catalyst that contains the adamantylimido ligand (1b, entry 8) is almost as successful as 1a.

TABLE 1 Ethenolysis of methyl oleate (MO). P Time Entry Catalyst Eq. (atm) (h) % Conv.^(a) % Select.^(b) % Yield^(c) TON^(d) 1 Mo(NAr)(CHCMe₂Ph)(Me₂pyr)(OBitet) 500 4 1 94 >99 94 470 (1a) 2 1a 1000 4 20 80 >99 80 800 3 1a 5000 4 15 or 58 >99 58 2900 48 4 1a 5000 10 15 95 >99 95 4750 5 Mo(NAr)(CHCMe₂Ph)[OCMe(CF₃)₂]₂ 500 4 2 83 76 63 315 6 Mo(NAr)(CHCMe₂Ph)(Me₂pyr)(TPP) 500 4 20 87 86 75 325 7 Mo(NAr)(CHCMe₂Ph)(Me₂pyr)(OSiPh₃) 500 4 1 86 92 79 395 8 Mo(NAd)(CHCMe₂Ph)(Me₂pyr)(OBitet) 500 4 18 96 98 94 470 (1b) 9 W(NAr)(C₃H₆)(Me₂pyr)(OBitet) 500 4 17 48 >99 48 240 10 W(NAr)(C₃H₆)(Me₂pyr)(OBitet) (50° C.) 500 4 4 18 >99 62 310

In Table 1, (a) Conversion was calculated by =100−[(final moles of MO)×100/(initial moles of MO)]; (b) Selectivity was calculated by =(1D+M9D)×100/(total products); (c) Yield was calculated by =(1D or M9D)×100/(initial moles of MO); and TON was calculated by =percent yield[(moles of MO)/(moles catalyst)]. Abbreviations: Ar=2,6-i-Pr₂C₆H₃; Ad=1-adamantyl; HIPTO=hexaisopropylterphenoxide; TPP=2,3,5,6-Ph₄C₆H; Me₂Pyr=2,5-dimethylpyrrolide; and Bitet is the aryl group shown in FIG. 2 in compound 1a.

Tungstacyclobutane catalysts (entries 9 and 10) produced results that were inferior to molybdenum catalysts in yield, either at room temperature or at 50° C., although selectivity was still >99%. Without wishing to be bound by theory, since it is likely that the rate limiting step in ethenolysis is loss of ethylene from an unsubstituted metallacyclobutane, one possible reason why tungsten is slower than molybdenum is that tungstacyclobutanes release ethylene more slowly than molybdacyclobutanes. Another possibility is that the ester carbonyl binds to tungsten more strongly than it does to molybdenum and inhibits turnover to a more significant degree.

Ethenolysis of 30000 equiv of cyclooctene to give 1,9-decadiene with 1a as the catalyst proceeded with a TON of 22500 (75% yield) at 20 atm (Table 2). Initiation of polymerization of cyclooctene with 1a may be slow, so little 1a is consumed before it reacts with ethylene to yield Mo(NAr)(CH₂)(Me₂Pyr)(OBitet), and ethenolysis then proceeds rapidly. At 1 atm of ethylene in an NMR scale reaction, poly(cyclooctene) is observed, but the amount of polymer decreases substantially upon addition of more ethylene. Essentially the same result as shown in entry 5 was observed when commercial 99.995% ethylene was employed. Therefore impurities in ethylene do not appear to limit TON.

TABLE 2 Ethenolysis of cyclooctene with 1a. % % % Entry Equiv. P (atm) Time (hr) Conv. Yield Select. TON 1 5000 10 16 98 90 92 4500 2 10000 10 20 98 80 82 8000 3 10000 20 20 93 93 >99 9300 4 20000 20 16 88 88 >99 17600 5 30000 20 20 75 75 >99 22500

Ethenolysis of 5000 equivalents of cyclopentene at 20 atm of 99.5% ethylene leads to 84% conversion to 1,6-heptadiene in 79% yield in 15 h (TON 3950). In a run employing 10000 equivalents of cyclopentene and 99.995% ethylene the yield is 58% and TON 5800 in 20 h. It should be noted that the cost of 1,6-heptadiene in small quantities from a typical commercial source is approximately two orders of magnitude greater than the cost of cyclopentene plus ethylene.

EXAMPLE 2

The following example provides information regarding the methods and materials employed in Example 1.

General. All manipulations of air and moisture sensitive materials were conducted under a nitrogen atmosphere in a Vacuum Atmospheres drybox or on a dual-manifold Schlenk line. The glassware, including NMR tubes were oven-dried prior to use. Ether, pentane, toluene, dichloromethane, toluene and benzene were degassed with dinitrogen and passed through activated alumina columns and stored over 4 Å Linde-type molecular sieves. Dimethoxyethane, cyclooctene, and cyclopentene were vacuum distilled from a dark purple solution of sodium benzophenone ketyl, and degassed three times by freeze-pump-thaw technique. The deuterated solvents were dried over 4 Å Linde-type molecular sieves prior to use. ¹H and ¹³C NMR spectra were acquired at room temperature unless otherwise noted using Varian spectrometers and referenced to the residual ¹H/¹³C resonances of the deuterated solvent (¹H: CDCl₃, δ 7.26; C₆D₆, δ 7.16; CD₂Cl₂, δ 5.32; C₇D₈, δ 7.09, 7.00, 6.98, 2.09. ¹³C: CDCl₃, δ 77.23; C₆D₆, δ 128.39; CD₂Cl₂, δ 54.00; C₇D₈, δ 137.86, 129.24, 128.33, 125.49, 20.4) and are reported as parts per million relative to tetramethylsilane. The elemental analysis was performed by Midwest Microlab, Indianapolis, Ind. The high pressure vessel equipped with a pressure gauge was purchased from Parr Instrument Company, Moline, Ill.

General Ethenolysis Procedure. Ethenolysis reactions were set up under an inert atmosphere in a glovebox: a Fisher-Porter bottle or a high pressure vessel equipped with a stir bar was charged with the appropriate amount of olefin (methyl oleate, cyclooctene, or cyclopentene) and with a mesitylene solution of the olefin metathesis catalyst of the desired concentration and volume. The mesitylene was used as internal standard. The head of the Fisher-Porter bottle equipped with a pressure gauge was adapted on the bottle. The system was sealed and taken out of the glovebox to an ethylene line. The vessel was then pressurized to the desired pressure. The reaction mixture was stirred at room temperature overnight. The reactions were then quenched with 10 uL (microliters) of 2-bromo-benzaldehyde and analyzed by gas chromatography (GC). Benzene was used as solvent for the ethenolysis reactions with 50 and 500 equiv of substrate. All the other runs were performed neat. For each entry, two identical reactions were performed and the data were averaged.

GC Analytical Method for Methyl Oleate. The GC analyses were run using a flame ionization detector (FID). Column: Rtx-1 from Restek; 30 m×0.25 mm (i d)×1.0 um (micrometer) film thickness. GC and column conditions: injector temperature 250° C.; detector temperature 250° C.; oven temperature, starting temperature 100° C., hold 5 min, ramp rate 10° C./min to 200° C., hold time 0 min; ramp rate 50° C/min to 300° C., hold time 8 min; carrier gas nitrogen.

GC Analytical Method for Cyclooctene and Cyclopentene. The GC analyses were run using a flame ionization detector (FID). Column: HP-5 (Crosslinked 5% PH ME Siloxane); 30 m×0.32 mm (i.d.)×0.25 um film thickness. GC and column conditions: injector temperature 350° C.; detector temperature 350° C.; oven temperature 50° C.; carrier gas nitrogen.

Materials. Mo(NAr)(CHCMe₂Ph)(Me₂Pyr)₂ (Singh, R.; Czekelius, C.; Schrock, R. R.; Müller, P.; Hoveyda, A. H. Organometallics, 2007, 26, 2528), Mo(NAr)(CHCMe₂Ph)[OCMe(CF₃)₂]₂ (Bazan, G. C.; Oskam, J H.; Cho, H. N.; Park, L. Y.; Schrock, R. R. J. Am. Chem. Soc., 1991, 113, 6899.), Mo(NAr)(CHCMe₂Ph)(Me₂Pyr)(TPP) (Lee, Y.-J.; Schrock, R. R.; Hoveyda, A. H. J. Am. Chem. Soc., 2009, online 07/06), (R)— and (S)—Mo(NAr)(CHCMe₂Ph)(Me₂Pyr)(OBitet) (1a) ((a) Malcolmson, S. J.; Meek, S. J.; Sattely, E. S.; Schrock, R. R.; Hoveyda, A. H. Nature, 2008, 456, 933; (b) Sattely, E. S.; Meek, S. J.; Malcolmson, S. J.; Schrock, R. R.; Hoveyda, A. H. J. Am. Chem. Soc., 2009, 131, 943), Mo(NAd)(CHCMe₂Ph)(Me₂Pyr)(OBitet) (1b) (Ibrahem, I.; Yu, M.; Schrock, R. R.; Hoveyda, A. H. J. Am. Chem. Soc., 2009, 131, 3844), Mo(NAd)(CHCMe₂Ph)(Me₂Pyr)(TPP) (Flook, M. M.; Jiang, A. J.; Schrock, R. R.; Muller, P.; Hoveyda, A. H. J. Am. Chem. Soc., 2009, 131, 7962), Mo(NAd)(CHCMe₂Ph)(pyr)(HIPTO) (2a) (Flook, M. M.; Jiang, A. J.; Schrock, R. R.; Müller, P.; Hoveyda, A. H. J. Am. Chem. Soc., 2009, 131, 7962), and W(NAr)(C₃H₆)(Me₂Pyr)(OBitet) (Jiang, A. J.; Simpson, J. H.; Muller, P.; Schrock, R. R. J. Am. Chem. Soc., 2009, 131, 7770) were prepared as described in the literature.

Preparation of Mo(NAr)(CHCMe₂Ph)(2,5-Me₂NC₄H₂)(OSiPh₃). A cold solution of Ph₃SiOH (149 mg, 0.54 mmol, 1 equiv) in 5 mL diethyl ether was added dropwise to a cold solution of Mo(NAr)(CHCMe₂Ph)(2,5-Me₂NC₄H₂)₂ (319 mg, 0.54 mmol, 1 equiv) in 5 mL diethylether. The reaction mixture was stirred at room temperature for 30 min The volatile materials were removed under vacuum. The orange solid generated was recrystallized from diethylether to obtain 259 mg of orange crystals (yield=62%). ¹H NMR (500 MHz, CD₂Cl₂) δ 11.85 (s, 1H, syn Mo=CH, J_(CH)=120.4 Hz), 7.54-7.08 (m, 23H, Ar), 5.79 (s, 2H, NC₄H₂), 3.72 (sept, 2H, MeCHMe, J=7.0 Hz), 2.11 (s, 6H), CH₃), 1.62 (s, 3H, CH₃), 1.52 (s, 3H, CH₃), 1.06 (app d, 6H, MeCHMe), 0.96 (br, 6H, MeCHMe); ¹³C NMR (125 MHz, CD₂Cl₂) δ 286.7, 153.4, 148.6, 147.5, 136.4, 135.7, 135.5, 130.6, 130.4, 128.6, 128.4, 126.5, 126.3, 123.5, 109.7, 108.9, 108.1, 54.9, 31.9, 30.6, 30.4, 29.1, 23.8 (br), 17.3 (br). Anal. Calc'd for C₄₆H₅₂MoN₂OSi: C, 71.48; H, 6.78; N, 3.62; Found: C, 71.44; H, 6.69; N, 3.75.

Preparation of (S)— and (R)—Mo(NAr)(CH₂)(Me₂Pyr)(OBitet). Ethylene (1 equiv) was added to a solution of (S)-1a (25.5 mg, 1 equiv) in C₇D₈ (40 mM). The ¹H NMR was recorded after 5 minutes at 10° C. The two methylidenes are observed in the ratio of 2:1. ¹H NMR (500 MHz, C₇D₈, 10° C.) selected peaks δ 67% dH_(alpha)=12.35 (d, 1H, Mo═CH, J_(HH)=4.5 Hz), 12.13 (d, 1H, Mo═CH, J_(HH)=4.5 Hz); 33% at 10° C., dH_(alpha)=12.94 (d, 1H, Mo═CH, J_(HH)=4.0 Hz), 12.24 (d, 1H, Mo═CH, J_(HH)=4.0 Hz); When ¹³C₂H₄ was used, the following ¹³C NMR was observed. ¹³C NMR (125 MHz, C₇D₈, 10° C.) selected peaks δ 276.3 (Mo═CH₂), 275.9 (Mo═CH₂).

Preparation of Mo(NAr)(CH₂CH₂CH₂)(Me₂Pyr)(OBitet). Ethylene (1 atm) was added to a pentane solution of Mo(NAr)(CHCMe₃)(Me₂Pyr)(OBitet) (25.5 mg, 40 mM) in a J. Young tube. The reaction mixture was allowed to cool down to −78° C. The volatile materials were removed under vacuum at −78° C. A 1:1 mixture of pentane:tetramethylsilane was vacuum transferred at −78° C. Ethylene (1 atm) was added to the J. Young tube at 20° C. The solution was stored at −30° C. Orange crystals of Mo(NAr)(CH₂CH₂CH₂)(Me₂Pyr)(OBitet) (10 mg) were isolated in 40% yield. ¹H NMR (500 MHz, C₇D₈, −70° C.) selected peaks dH_(alpha)=6.16, 5.69, 5.24, 5.03; dH_(beta)=0.74,-0.16. ¹³C NMR (125 MHz, C₇D₈, −70° C.) selected peaks dC_(alpha)=102.2, 101.2; dC_(beta)=−1.1. Anal. Calc'd for C₄₇H₆₄Br₂MoN₂O₂Si: C, 58.03; H, 6.63; N, 2.88; Found: C, 57.64; H, 6.77; N, 2.85. X-Ray quality crystals were grown from a mixture of pentane and tetramethylsilane at −30° C. and under 1 atm of ethylene.

While several embodiments of the present invention have been described and illustrated herein, those of ordinary skill in the art will readily envision a variety of other means and/or structures for performing the functions and/or obtaining the results and/or one or more of the advantages described herein, and each of such variations and/or modifications is deemed to be within the scope of the present invention. More generally, those skilled in the art will readily appreciate that all parameters, dimensions, materials, and configurations described herein are meant to be exemplary and that the actual parameters, dimensions, materials, and/or configurations will depend upon the specific application or applications for which the teachings of the present invention is/are used. Those skilled in the art will recognize, or be able to ascertain using no more than routine experimentation, many equivalents to the specific embodiments of the invention described herein. It is, therefore, to be understood that the foregoing embodiments are presented by way of example only and that, within the scope of the appended claims and equivalents thereto, the invention may be practiced otherwise than as specifically described and claimed. The present invention is directed to each individual feature, system, article, material, kit, and/or method described herein. In addition, any combination of two or more such features, systems, articles, materials, kits, and/or methods, if such features, systems, articles, materials, kits, and/or methods are not mutually inconsistent, is included within the scope of the present invention.

The indefinite articles “a” and “an,” as used herein in the specification and in the claims, unless clearly indicated to the contrary, should be understood to mean “at least one.”

The phrase “and/or,” as used herein in the specification and in the claims, should be understood to mean “either or both” of the elements so conjoined, i.e., elements that are conjunctively present in some cases and disjunctively present in other cases. Other elements may optionally be present other than the elements specifically identified by the “and/or” clause, whether related or unrelated to those elements specifically identified unless clearly indicated to the contrary. Thus, as a non-limiting example, a reference to “A and/or B,” when used in conjunction with open-ended language such as “comprising” can refer, in one embodiment, to A without B (optionally including elements other than B); in another embodiment, to B without A (optionally including elements other than A); in yet another embodiment, to both A and B (optionally including other elements); etc.

As used herein in the specification and in the claims, “or” should be understood to have the same meaning as “and/or” as defined above. For example, when separating items in a list, “or” or “and/or” shall be interpreted as being inclusive, i.e., the inclusion of at least one, but also including more than one, of a number or list of elements, and, optionally, additional unlisted items. Only terms clearly indicated to the contrary, such as “only one of or “exactly one of,” or, when used in the claims, “consisting of,” will refer to the inclusion of exactly one element of a number or list of elements. In general, the term “or” as used herein shall only be interpreted as indicating exclusive alternatives (i.e. “one or the other but not both”) when preceded by terms of exclusivity, such as “either,” “one of,” “only one of,” or “exactly one of.” “Consisting essentially of,” when used in the claims, shall have its ordinary meaning as used in the field of patent law.

As used herein in the specification and in the claims, the phrase “at least one,” in reference to a list of one or more elements, should be understood to mean at least one element selected from any one or more of the elements in the list of elements, but not necessarily including at least one of each and every element specifically listed within the list of elements and not excluding any combinations of elements in the list of elements. This definition also allows that elements may optionally be present other than the elements specifically identified within the list of elements to which the phrase “at least one” refers, whether related or unrelated to those elements specifically identified. Thus, as a non-limiting example, “at least one of A and B” (or, equivalently, “at least one of A or B,” or, equivalently “at least one of A and/or B”) can refer, in one embodiment, to at least one, optionally including more than one, A, with no B present (and optionally including elements other than B); in another embodiment, to at least one, optionally including more than one, B, with no A present (and optionally including elements other than A); in yet another embodiment, to at least one, optionally including more than one, A, and at least one, optionally including more than one, B (and optionally including other elements); etc.

In the claims, as well as in the specification above, all transitional phrases such as “comprising,” “including,” “carrying,” “having,” “containing,” “involving,” “holding,” and the like are to be understood to be open-ended, i.e., to mean including but not limited to. Only the transitional phrases “consisting of” and “consisting essentially of” shall be closed or semi-closed transitional phrases, respectively, as set forth in the United States Patent Office Manual of Patent Examining Procedures, Section 2111.03. 

1. A method, comprising: reacting ethylene and a first species comprising at least one internal olefin in the presence of a transition metal catalyst to produce at least one product comprising a double bond, the double bond comprising a carbon atom from the ethylene and an atom of the first species, wherein the at least one product is formed at a turnover number of at least about 5000, a selectivity of at least about 80%, and a conversion of at least about 70%.
 2. The method of claim 1, wherein the turnover number is at least about 10,000.
 3. The method of claim 1, wherein the turnover number is at least about 15,000.
 4. The method of claim 1, wherein the turnover number is at least about 20,000.
 5. The method of claim 1, wherein the turnover number is at least about 25,000.
 6. The method of claim 1, wherein the selectivity is at least about 85%.
 7. The method of claim 1, wherein the selectivity is at least about 90%.
 8. The method of claim 1, wherein the selectivity is at least about 95%.
 9. The method of claim 1, wherein the selectivity is at least about 97%.
 10. The method of claim 1, wherein the conversion is at least about 75%.
 11. The method of claim 1, wherein the conversion is at least about 80%.
 12. The method of claim 1, wherein the conversion is at least about 85%.
 13. The method of claim 1, wherein the conversion is at least about 90%.
 14. The method of claim 1, wherein the conversion is at least about 95%.
 15. The method of claim 1, wherein the transition metal catalyst comprises molybdenum or tungsten.
 16. The method of claim 1, wherein the atom of the first species is carbon.
 17. The method of claim 1, wherein the first species comprising at least one internal olefin is cyclic.
 18. The method of claim 1, wherein the first species comprising at least one internal olefin is non-cyclic.
 19. The method of claim 1, wherein the first species comprising at least one internal olefin is symmetric.
 20. The method of claim 1, wherein the first species comprising at least one internal olefin is non-symmetric.
 21. The method of claim 1, wherein the first species comprising at least one internal olefin comprises at least one heteroatom.
 22. The method of claim 1, wherein the first species comprising at least one internal olefin comprises at least two double bonds.
 23. The method of claim 1, wherein the first species comprising an internal olefin is methyl oleate.
 24. The method of claim 23, wherein the at least one product formed comprises 1-decene and methyl-9-decenoate.
 25. A method, comprising: providing a catalyst having the structure:

wherein M is Mo or W; R¹ is aryl, heteroaryl, alkyl, heteroalkyl, optionally substituted; R² and R³ can be the same or different and are hydrogen, alkyl, alkenyl, heteroalkyl, heteroalkenyl, aryl, or heteroaryl, optionally substituted; and R⁴ and R⁵ can be the same or different and are alkyl, heteroalkyl, aryl, heteroaryl, or silyl, optionally substituted, wherein at least one of R⁴ or R⁵ is a ligand containing oxygen bound to M; and reacting ethylene and a first species comprising at least one internal olefin in the presence of the catalyst to produce at least one product comprising a double bond, the double bond comprising a carbon atom from the ethylene and an atom of the first species, wherein the at least one product is formed at a turnover number of at least about
 500. 26. The method of claim 25, wherein one of R⁴ and R⁵ is a ligand containing oxygen bound to M, optionally substituted, and the other is a ligand containing nitrogen bound to M, optionally substituted.
 27. The method of claim 25, wherein the at least one ligand containing oxygen bound to M lacks a plane of symmetry.
 28. The method of claim 26, wherein the ligand containing nitrogen bound to M is selected from the group consisting of pyrrolyl, pyrazolyl, pyridinyl, pyrazinyl, pyrimidinyl, imidazolyl, triazolyl, tetrazolyl, oxazolyl, isoxazolyl, thiazolyl, isothiazolyl, indolyl, indazolyl, carbazolyl, morpholinyl, piperidinyl, and oxazinyl, all optionally substituted
 29. The method of claim 25, wherein the first species comprising at least one internal olefin is methyl oleate.
 30. The method of claim 29, wherein the at least one product formed comprises 1-decene and methyl-9-decenoate.
 31. The method of claim 26, wherein: R¹ and R² are the same or different and are aryl or alkyl, optionally substituted; and R³ is hydrogen.
 32. The method of claim 26, wherein the ligand containing nitrogen bound to M has the structure:

wherein each R⁶ can be the same or different and is hydrogen, alkyl, heteroalkyl, aryl, or heteroaryl, optionally substituted; and X may be present or absent and is any non-interfering group.
 33. The method of claim 25, wherein the ligand containing oxygen bound to M has the following structure:

wherein R⁷ is aryl, heteroaryl, alkyl, or heteroalkyl, optionally substituted; R⁸ is hydrogen, —OH, halogen, alkyl, heteroalkyl, aryl, heteroaryl, acyl, acyloxy, or —OP, optionally substituted; or, together R⁷ and R⁸ are joined to form a ring, optionally substituted; R⁹ is —OH, —OP, or amino, optionally substituted; R¹⁰ is hydrogen, halogen, alkyl, heteroalkyl, aryl, heteroaryl, or acyl, optionally substituted; each R¹¹, R¹², R¹³ and R¹⁴ can be the same or different and is aryl, heteroaryl, alkyl, heteroalkyl, or acyl, optionally substituted; or, together R¹¹ and R¹² are joined to form a ring, optionally substituted; or together R¹³ and R¹⁴ are joined to form a ring, optionally substituted; and P is a protecting group.
 34. The method as in claim 25, wherein R⁴ is silyl-protected BINOL derivative.
 35. The method as in claim 25, wherein R¹ is:

wherein each R¹⁷ can be the same or different and is hydrogen, halogen, alkyl, heteroalkyl, aryl, acyl, or —OP, optionally substituted; and P is a protecting group.
 36. The method as in claim 25, wherein R¹ is

wherein each R¹⁷ can be the same or different and is hydrogen, halogen, alkyl, heteroalkyl, aryl, acyl, or —OP, optionally substituted; and P is a protecting group.
 37. The method as in claim 25, wherein R² is alkyl.
 38. The method as in claim 21, wherein R¹ is

wherein each 1e can be the same or different and is hydrogen, halogen, alkyl, heteroalkyl, aryl, acyl, or —OP, optionally substituted; R² is CMe₂Ph or CMe₃; R³ is H; and R⁴ is an enantiomer of the following structure,

wherein each R⁷ and R¹⁰ is the same or different and is halogen, methyl, t-butyl, CF₃, or aryl, optionally substituted; and P is a protecting group.
 39. The method as in claim 38, wherein R⁵ has the following structure:

and Wherein each R⁶ can be the same or different and is hydrogen, alkyl, heteroalkyl, aryl, heteroaryl, optionally substituted; and X may be present or absent and is any non-interfering group.
 40. The method of claim 25, wherein the ligand containing oxygen bound to M has the following structure:

wherein each R⁷ and R⁸ can be the same or different and is hydrogen, halogen, alkyl, alkoxy, aryl, acyl, or a protecting group, optionally substituted; R¹⁰ is hydrogen, halogen, alkyl, heteroalkyl, aryl, heteroaryl, or acyl, optionally substituted; each R¹¹, R¹², R¹³ and R¹⁴ can be the same or different and is aryl, heteroaryl, alkyl, heteroalkyl, or acyl, optionally substituted; or, together R¹¹ and R¹² are joined to form a ring, optionally substituted; or, together R¹³ and R¹⁴ are joined to form a ring, optionally substituted; R¹⁵ is alkyl, aryl, or a protection group, optionally substituted; R¹⁶ is hydrogen or an amine protecting group; X can be any non-interfering group; each Z can be the same or different and is (CH₂)_(m), N, O, optionally substituted; n is 0-5; and m is 1-4.
 41. The method of claim 40, wherein R⁷ and R¹⁰ are the same or different and is selected from the group consisting of F, Cl, Br, or I.
 42. The method of claim 25, wherein R² is CMe₂Ph or CMe₃ and R³ is hydrogen.
 43. The method of claim 25, wherein M is Mo.
 44. The method of claim 25, wherein the atom of the first species is carbon.
 45. The method of claim 25, wherein the turnover number is at least about 1,000.
 46. The method of claim 25, wherein the turnover number is at least about 5,000.
 47. The method of claim 25, wherein the turnover number is at least about 10,000.
 48. The method of claim 25, wherein the at least one product is formed at a selectivity of at least about 80%.
 49. The method of claim 25, wherein the at least one product is formed at a selectivity of at least about 90%.
 50. The method of claim 25, wherein the at least one product is formed at a selectivity of at least about 95%.
 51. The method of claim 25, wherein the at least one product is formed at a conversion of at least about 60%.
 52. The method of claim 25, wherein the at least one product is formed at a conversion of at least about 70%.
 53. The method of claim 25, wherein the at least one product is formed at a conversion of at least about 80%.
 54. The method of claim 25, wherein the at least one product is formed at a conversion of at least about 90%. 